Method and apparatus of quantitative non-resonant photoionization of neutral particles and the use of such apparatus

摘要

A method and an apparatus for non-resonant photoionization of multiple species of neutral particles of a gas in which the neutral particles are ionized in an ionization space by a laser beam having a maximum intensity above the saturation intensity for ionizing neutral particles of multiple desired types. The ions so produced are extracted from the ionization space by an ion-optical system. The ionization of the desired types of neutral particles and/or the extraction of the produced ions are confined by light-optical or ion-optical means to a sharply limited space in which the intensity of the laser beam is above the saturation intensity or is negligibly low with respect to the ionization of neutral particles of interest, so that the number of extracted ions of the ion type of interest does not substantially increase when the laser beam intensity is further increased. The multiple ionized species can be quantitatively determined mass spectrographically in a single step.